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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,831 
If I have 2 electrical adapters for a specific device, which has the following information on them:
1...

Jan708 08:40 AM
Shooting Star

6 
2,060 
We have bees flying in a jar, not touching it. Jar is closed and air in it has standard atmospheric pressure. Here is...

Jan608 05:35 PM
russ_watters

43 
23,329 
consider a symmetrical solid body. we say its centre of mass is at its geometric centre. that is, for uniform density...

Jan608 12:29 PM
arildno

1 
12,004 
The General Information about the game:
The law of the Football game says that the ball should be a sphere of leather...

Jan608 11:11 AM
vidhatanand

0 
6,385 
Hi Newbie here so please go easy on me..!
To keep this within my ability to understand can we please live in the...

Jan608 09:45 AM
44HP

6 
1,881 
Hi,
I am having two doubts about the fringing field capacitance.
1) In most of the formulae, the fringing...

Jan608 03:55 AM
Dekar

0 
11,128 
I've unsuccessfully been looking for a decent proof of Chasles' Theorem which states that any rigid body displacement...

Jan508 09:51 PM
EFuzzy

4 
6,484 
Hello
I've been reading optics (both the cartesian and real/virtual sign convention) and I have some queries:
1....

Jan508 03:02 AM
zimrock

14 
3,284 
Can anyone tell me how to i can calculate the amount of load an electromagnet will pull. the electro magnet has 3...

Jan508 12:56 AM
amit_sarda

3 
1,462 
There was an interesting problem that appeared in POPTOR 2005:
A generator consists of a parallelplate capacitor...

Jan308 07:38 PM
Troels

3 
3,965 
I heard that one can solve 2D problem with conformal mapping of complex numbers.
Is it possible to use this method...

Jan308 03:22 PM
marcusl

3 
3,647 
Hi, the physics department at my (undergrad) college is looking around for a good Thermodynamics book for next...

Jan308 01:22 PM
mbrmbrg

1 
3,163 
I've only just completed high school, but I have a decent grasp on basic undergrad maths/physics. After hours and...

Jan308 01:57 AM
Shooting Star

28 
3,112 
Is there any physical law that prohibits the continuous generation of a reactionless torque using a series of...

Jan208 04:33 PM
russ_watters

1 
3,288 
what exactly is the cutoff ratio, in physical terms?

Jan208 03:57 PM
brewnog

2 
3,790 
I searched for this and get conflicting results. I have setup a demonstration that has a erlymeyer flask with a one...

Jan208 01:11 PM
paul k

10 
3,335 
I have a simple question about work. Work is force times distance, in the direction that the force is applied. So...

Dec3107 08:47 PM
Robert100

10 
7,061 
Why is the above notation used instead of Sum_x Exp(b H(x))? Does the "Tr" notation above have anything in common...

Dec3107 04:37 PM
YaroslavVB

12 
3,286 
can anyone proove "kelvin plank" statement of second law of thermodynamics or atleast show that it is always followed...

Dec3107 07:47 AM
sadhu

4 
3,182 
Hi all,
I'm posting here because I see an apparent paradox between what intuition and equations tell me. I'm sure...

Dec3107 02:11 AM
animalcroc

7 
2,407 
Hello, I was recently browsing through on of my physics books, and I came upon the following statement:
"Newton was...

Dec3007 06:19 PM
Integral

2 
1,850 
So.. we've got a 2D crystal, corresponding an infinite square net with +e0 charges in each one (see the atached...

Dec3007 04:40 AM
Istvan

2 
3,183 
why is there a factor of 1/4 in front of the two tensors? Is it formulated that way for convenience?

Dec2907 11:29 PM
Parlyne

1 
3,759 
According to Noether's Theorem, for every symmetry of the Lagrangian there is a corresponding conservation law. For...

Dec2807 10:58 PM
Rainbow Child

1 
1,880 
Can anyone tell me where the 4*pi comes from in coulomb's law? I know the law is often compared to netwon's law of...

Dec2807 07:04 PM
rbj

7 
8,869 
Hi
I need to prove Maxwell's second equation \nabla\bulletB=0
I tried few things, but never came with result... and...

Dec2807 06:23 PM
ZapperZ

14 
3,406 
a problem.....pls check..
imagine theres a horizontal planeA bove which the effects of gravity are not felt. any...

Dec2707 01:19 PM
Himanshu

50 
8,719 
Hi folks, I have a problem that I am trying to figure out that I hope you can help me with. I don't want to be spoon...

Dec2607 10:28 PM
shiftless

4 
1,700 
Hello, is it possible to figure out how much force in newtons is created when a compressed gas expands?

Dec2607 03:55 PM
russ_watters

6 
7,003 
we know that during inelastic collision momentum remain conserved but kinetic energy of system does not
some part of ...

Dec2607 03:19 PM
Shooting Star

12 
2,360 
do gravitational field lines always need to be straight, cant they be just curves
if yes then please tell an...

Dec2607 12:56 PM
sadhu

2 
1,607 
What does the term "Action" means in physics?

Dec2607 12:04 PM
belliott4488

9 
1,888 
how does a transformer work?

Dec2607 01:00 AM
rbj

5 
3,807 
Does anyone know of an experiment that shows that the electrostatic and/or magnetostatic forces have a finite speed,...

Dec2607 12:46 AM
rbj

2 
1,696 
When they say K=1/2mv^2 does K mean the change of kinetic energy? because Wtotal= the change of kinetic energy...

Dec2507 10:59 PM
sadhu

2 
1,735 
hello all, i've been researching a bit of info on lens optics (image propagation mostly), but have only found...

Dec2507 08:27 PM
infamous_Q

0 
1,912 
Hi all,
I was giving a class on dilatation and I have proposed to the students a problem where two pieces of wire...

Dec2507 06:16 PM
DaTario

30 
3,425 

is it true that when the net force...

Dec2507 01:54 PM
Shooting Star

2 
1,781 
I want to find a solid argument why entropy always increases and even more important why it is
S=\sum_i p_i \ln p_i...

Dec2507 08:09 AM
Gerenuk

0 
1,773 
The Ampere's Law is \nabla \times B = \mu J and Gauss's Law is \nabla \cdot E = \frac{1}{\epsilon} \rho
Since J...

Dec2407 06:17 PM
G01

5 
2,168 